If the U.S.-backed aerial spraying of chemicals does not stop immediately, Colombia will pay a heavy price for environmental destruction and lost livelihoods in its indigenous communities, warns a new study by a U.S.-based environmental research group.

The 23-page study documents numerous cases of damage to human health, destruction of food crops and contamination of water that have occurred as a result of the six years of aerial spraying of chemicals.

The aerial spraying of coca crops is part of the U.S. government’s 1.2-billion-dollar Plan Colombia, which aims to target the supply side in order to deal with the problem of narcotic consumption at home.

Titled “Alternative development strategies: the need to move beyond illicit crop spraying,” the report shows that despite years of chemical spraying, both the U.S. and Colombian governments have failed to reduce coca production, which has remained relatively stable.

In 2000, the total area of coca crops was estimated to be around 163,000 hectares. Today, coca is grown on no less than 144,000 hectares, according to researchers, who relied both on independent and official sources.

“The aerial spraying has been completely ineffective and rather counterproductive,” Anna Cederstav, program director at the Oakland, California-based Inter-American Association for Environmental Defense (AIDA), told IPS.

AIDA researchers who authored the study say that nearly 90 percent of the farms affected by the hazardous chemical spraying were devoted to legal production of food crops, such as fruits, vegetables and organic coffee  not coca. Yet no one has been compensated for the damages.

Moreover, they point out that farms which are supported by the U.S. Agency for International Development (USAID) and the U.N. Office on Drugs and Crime (UNODC) as part of international efforts to provide alternate means of living to coca growers have also been hit by indiscriminate spraying.

In May and June last year, for example, coca farms in the southeastern region were sprayed even though many other legal farmers in the area had obtained expensive organic certifications to sell their harvest on the international market.

The study notes that in many cases, indigenous and Afro-Colombian communities were not consulted by the authorities responsible for spraying, even though they were required by Colombian and international law to do so.

In Colombia, many indigenous communities are believed to be supportive of Marxist guerrillas associated with the Revolutionary Armed Forces of Colombia (FARC), who have been at war the government in Bogotá and the right-wing paramilitary militias for the past 40 years.

Those closely monitoring the political conflict in Colombia have often pointed to the involvement of FARC and the paramilitaries in the illegal trade in coca production and refined cocaine to the United States and Europe, but both sides have dismissed such claims.

Comparing the lack of results of the U.S.-backed spraying program with the successes of community-based development program, the study suggests that there is a need for alternative development projects.

“There exist other successful programs to eradicate illicit crops that don’t have as high economic, social, environmental and health costs as the spraying effort,” said Rafael Colmenares, director of Ecofondo, an umbrella group representing more than 130 environmental organizations in Colombia.

To him, “it is these programs that should be backed, as they can bring a real, lasting solution to this problem.”